North American Database of Archaeological Geophysics
Graphic/Image:
Project Name: Petaluma Adobe State Historic Park (CA-Son-2294/H), CA;
Reference: Silliman, S.W., Farnsworth, P., and K.G. Lightfoot (2000). Magnetometer Prospecting in Historical Archaeology: Evaluating Survey Options at a 19th-Century Rancho Site in California. Historical Archaeology 34(2):89-109. (used with permission).
Silliman, S.W. (2000). Colonial Worlds, Indigenous Practices: The Archaeology of Labor on a 19th-Century California Rancho. Ph.D. Disseration, University of California-Berkeley.
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Comparison of alkali-vapor gradiometer images by resolution. a: 1.0 x 0.05 m sampling interval, 0.75 nT/m contour interval, range of -50-50 nT/m. b: 1.0 x 0.1 m sampling interval, 0.5 nT/m contour interval, range of -35-50 nT/m. The linear cobble feature represents fluvial deposits beneath the historic cultural deposits. The refuse features consisted of fire-cracked rock and metal objects in addition to a variety of non-metallic artifacts.
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